1. Field of the Invention
The present invention relates to a detector agent for halogen compounds, which contains curcumin or Bromocresol Green as a discoloring component, and a method for detecting halogen compounds by use of said detector agent, and the present invention is usual to judge the leakage of halogen compounds which are used in a semiconductor-manufacturing plant or the like or the break-though of a solid treatment agent for removal of harmful substances.
2. Description of the Related Art
Gases containing halogen compounds such as F2, Cl2, FCl3, HF, BrF5 and SiCl4 are useful in many applications, for instance, in a field of chemical industries including a semiconductor-manufacturing plant so as to utilize a higher reactivity of halogen atoms. In a case where they are used, various halogen compounds are produced as their reaction products. These halogen compounds possess in many cases a higher reactivity, in which their danger and toxicity are intensive. Accordingly, it is not permitted to release gases containing these halogen compounds as they are, and it is desired to release them to the atmosphere after they are made harmless by a harmful substances removal apparatus.
As such a harmful substances removal apparatus as mentioned above, there have been known apparatuses for removing or decomposing halogen compounds through a wet treatment such as an alkali scrubber or a dry treatment using a solid treatment agent such as a decomposition catalyst, solid reaction agent or adsorbent. In a case where a solid treatment agent is used, it is necessary to detect halogen compounds on the downstream side thereof so that the deterioration of the solid treatment agent is judged because it has a life time (a break-though time) determined by its catalyst poisoning, reactive deterioration or adsorptive saturation.
As for a method for detecting halogen compounds, a method of using a detector agent which is discolored due to the presence of halogen compounds is simple. There has been known, for example, a detector agent containing a molybdate as a discoloring component for dichlorosilane.
For various halogen compounds which are used in a semiconductor-manufacturing plant or the like, however, there has not been known till now a detector agent which is effectively discolored at a lower concentration. In addition, curcumin or Bromocresol Green has been known only as a discoloring component for the detection of boron or the indication of pH.
It is therefore an object of the present invention to provide a detector agent which is effectively discolored at a lower concentration for various halogen compounds and a method for detecting halogen compounds by use of said detector agent.
In order to achieve the aforementioned purpose, the inventors have studied hard the usability of various kinds of coloring compounds, have found a fact that the aforementioned purpose can be achieved by using curcumin or Bromocresol Green as a discoloring component, and have completed the present invention.
Namely, the detector agent according to the present invention is a detector agent for halogen compounds, which contains curcumin as a discoloring component, or a detector agent for halogen compounds, which contains Bromocresol Green as a discoloring component.
In the above-mentioned detector agent, said discoloring component is preferably supported on granular activated alumina.
On the other hand, the detecting method according to the present invention is a method for detecting halogen compounds, which comprises bringing anyone of said detector agents into contact with a gas to be detected that may contain halogen compounds, as said detector agent is disposed on a position where it can be visually observed from the outside.
Furthermore, the detecting method according to the present invention is a method for detecting halogen compounds, which comprises visually observing from the outside anyone of said detector agents disposed on the upper layer of a solid treatment agent for removing or decomposing halogen compounds, as a gas to be treated is caused for treatment to flow from the bottom side of a container filled with said solid treatment agent, whereby halogen compounds are detected to judge the deterioration of said solid treatment agent.